package cn.trymore.core.util;

import java.awt.Graphics2D;   
import java.awt.Rectangle;   
import java.awt.RenderingHints;   
import java.awt.geom.AffineTransform;   
import java.awt.image.BufferedImage;   
import java.awt.image.ColorModel;   
import java.awt.image.WritableRaster;   
import java.io.File;   
import java.io.FileInputStream;   
import java.io.IOException;   
import java.io.InputStream;   
import javax.imageio.ImageIO;   
 
/**  
* 图片工具类，完成图片的截取  
*   
* @author inc062977  
*   
*/  
public class ImageHelper {   
   /**  
    * 实现图像的等比缩放  
    * @param source  
    * @param targetW  
    * @param targetH  
    * @return  
    */  
   private static BufferedImage resize(BufferedImage source, int targetW,   
           int targetH) {   
       // targetW，targetH 分别表示目标长和宽   
       int type = source.getType();   
       BufferedImage target = null;   
       double sx = (double) targetW / source.getWidth();   
       double sy = (double) targetH / source.getHeight();   
       // 这里想实现在 targetW，targetH范围内实现等比缩放。如果不需要等比缩放   
       // 则将下面的 if else语句注释即可   
       if (sx < sy) {   
           sx = sy;   
           targetW = (int) (sx * source.getWidth());   
       } else {   
           sy = sx;   
           targetH = (int) (sy * source.getHeight());   
       }   
       if (type == BufferedImage.TYPE_CUSTOM) { // handmade   
           ColorModel cm = source.getColorModel();   
           WritableRaster raster = cm.createCompatibleWritableRaster(targetW,   
                   targetH);   
           boolean alphaPremultiplied = cm.isAlphaPremultiplied();   
           target = new BufferedImage(cm, raster, alphaPremultiplied, null);   
       } else  
           target = new BufferedImage(targetW, targetH, type);   
       Graphics2D g = target.createGraphics();   
       // smoother than exlax:   
       g.setRenderingHint(RenderingHints.KEY_INTERPOLATION,   
               RenderingHints.VALUE_INTERPOLATION_BICUBIC);   
       g.drawRenderedImage(source, AffineTransform.getScaleInstance(sx, sy));   
       g.dispose();   
       return target;   
   }   
 
   /**  
    * 实现图像的等比缩放和缩放后的截取  
    * @param inFilePath 要截取文件的路径  
    * @param outFilePath 截取后输出的路径  
    * @param width 要截取宽度  
    * @param hight 要截取的高度  
    * @param proportion  
    * @throws Exception  
    */  
      
   public static void saveImageAsJpg(String inFilePath, String outFilePath,   
           int width, int hight, boolean proportion)throws Exception {   
	   
	    String toDir = outFilePath.substring(0,outFilePath.lastIndexOf(System.getProperty("file.separator")));
		File dirFile = new File(toDir);
		if(!dirFile.exists()){
			dirFile.mkdirs();
		}
		
        File file = new File(inFilePath);   
        InputStream in = new FileInputStream(file);   
        File saveFile = new File(outFilePath);   
 
       BufferedImage srcImage = ImageIO.read(in);   
       if (width > 0 || hight > 0) {   
           // 原图的大小   
           int sw = srcImage.getWidth();   
           int sh = srcImage.getHeight();   
           // 如果原图像的大小小于要缩放的图像大小，直接将要缩放的图像复制过去   
           if (sw > width && sh > hight) {   
               srcImage = resize(srcImage, width, hight);   
           } else {   
               String fileName = saveFile.getName();   
               String formatName = fileName.substring(fileName   
                       .lastIndexOf('.') + 1);   
               ImageIO.write(srcImage, formatName, saveFile);   
               return;   
           }   
       }   
       // 缩放后的图像的宽和高   
      int w = srcImage.getWidth();   
      int h = srcImage.getHeight();   
      // 如果缩放后的图像和要求的图像宽度一样，就对缩放的图像的高度进行截取   
      if (w == width) {   
          // 计算 X轴坐标   
          int x = 0;   
          int y = h / 2 - hight / 2;   
          saveSubImage(srcImage, new Rectangle(x, y, width, hight), saveFile);   
      }   
      // 否则如果是缩放后的图像的高度和要求的图像高度一样，就对缩放后的图像的宽度进行截取   
      else if (h == hight) {   
          // 计算X轴坐标   
          int x = w / 2 - width / 2;   
          int y = 0;   
          saveSubImage(srcImage, new Rectangle(x, y, width, hight), saveFile);   
      } 
      in.close();   
  }   
  /**  
   * 实现缩放后的截图  
   * @param image 缩放后的图像  
   * @param subImageBounds 要截取的子图的范围  
   * @param subImageFile 要保存的文件  
   * @throws IOException  
   */  
   private static void saveSubImage(BufferedImage image,   
          Rectangle subImageBounds, File subImageFile) throws IOException {   
      if (subImageBounds.x < 0 || subImageBounds.y < 0  
              || subImageBounds.width - subImageBounds.x > image.getWidth()   
              || subImageBounds.height - subImageBounds.y > image.getHeight()) {   
          System.out.println("Bad   subimage   bounds");   
          return;   
      }   
      BufferedImage subImage = image.getSubimage(subImageBounds.x,subImageBounds.y, subImageBounds.width, subImageBounds.height);   
      String fileName = subImageFile.getName();   
      String formatName = fileName.substring(fileName.lastIndexOf('.') + 1);   
      ImageIO.write(subImage, formatName, subImageFile);   
  }   
  
  public static void main(String[] args){
	  try {
		ImageHelper.saveImageAsJpg("D:\\x36zhao\\Personal\\Photos\\Headers\\100322103174eb36eba2d29dd9.jpg", "d:\\x36zhao\\desktop\\test.jpg", 600, 400, true);
	} catch (Exception e) {
		// TODO Auto-generated catch block
		e.printStackTrace();
	}
  }

}   



